StableX Whitepaper

Unified Basket

All currencies (USDC + CHFX + TRYB + SEKX) exist in one unified pool. This creates deep liquidity for all trading pairs and allows for direct swaps between any two currencies without intermediate steps.

SBX Token

When users deposit into the pool, they receive SBX tokens at a 1:1 ratio with USD value. SBX tokens represent a share of the entire pool and can be withdrawn as any supported currency (subject to asymmetric withdrawal rules).

Asymmetric Withdrawal

To maintain pool balance and incentivize regional stablecoin deposits:

• • Regional depositors: Can withdraw any regional stablecoin OR USDC
• • USDC depositors: Can only withdraw regional stablecoins (cannot withdraw USDC)

Unified APY

All depositors earn the same APY regardless of which currency they deposit. This APY is typically higher than what USDC alone would provide, as it represents a weighted average of yields from all currencies in the pool.

API-Based Price Feeds

Prices are queried off-chain via API and passed as parameters to contract functions. This approach provides better flexibility and lower gas costs compared to on-chain oracle queries.

• • No Onchain Queries: Removed dependency on Pyth Network onchain queries
• • Price Format: All prices in micro-USD (1e6 = $1.00)
• • Off-Chain Queries: Frontend queries API before submitting transactions
• • Parameter Passing: Prices passed as function parameters

Direct A→B Swaps (Infinity Pool Core)

Unlike traditional DEXs that require routing through intermediate tokens, StableX enables direct swaps between any two regional stablecoins. This is the core of the infinity pool concept.

• • No USD intermediate - direct exchange between regional stablecoins
• • Rate calculation: rate_A_to_B = price_B / price_A (both in USD/[CURRENCY] format)
• • Single fee applied based on target asset depth
• • True infinity pool mechanics - all assets in one unified pool
• • Prices passed as parameters - queried from API off-chain before transaction

Three-Tier Fee System (80%/30% Thresholds)

System Overview

StableX operates on a dual-chain architecture, leveraging both IOTA L1 (Move-based) and IOTA EVM (Solidity-based) to provide unified liquidity across chains. The system consists of pool contracts, bridge contracts, token contracts, and a relayer service that facilitates cross-chain transfers.

Component Diagram

Detailed breakdown of all system components and their interactions.

Bridge Flow

The bridge enables seamless token transfers between IOTA L1 and IOTA EVM, maintaining unified liquidity across both chains.

L1 → EVM (Lock → Mint)

1. User calls bridge_l1::lock_*() on L1 with token coin and recipient EVM address
2. L1 bridge locks tokens in escrow and emits LockEvent
3. Relayer watches L1 events and calls EVMBridge::mint() on EVM
4. EVM bridge mints wrapped tokens to recipient

EVM → L1 (Burn → Unlock)

1. User calls EVMBridge::burn() on EVM with token type, amount, and recipient L1 address
2. EVM bridge burns wrapped tokens and emits BurnEvent
3. Relayer watches EVM events and calls bridge_l1::unlock() on L1
4. L1 bridge unlocks tokens from escrow and transfers to recipient

L1 Components (Move-based)

• • Native tokens: CHFX, TRYB, SEKX, USDC, SBX
• • Pool contract: sbx_pool.move
• • Bridge contract: bridge_l1.move (locks/unlocks tokens)
• • Flash vault: flash_vault.move
• • Shared objects: Pool and Registry created as shared objects

EVM Components (Solidity-based)

• • ERC-20 tokens: CHFX, TRYB, SEKX, USDC, wSBX (wrapped SBX)
• • Pool contract: StableXPool.sol
• • Bridge contract: EVMBridge.sol (mints/burns wrapped tokens)
• • Standard ERC-20: All tokens follow ERC-20 standard

Unified Liquidity

While pools exist separately on L1 and EVM, they are bridged via cross-chain transfers, allowing users to access liquidity from either chain seamlessly.

Reentrancy Protection

All contracts implement reentrancy guards to prevent recursive calls and ensure atomic operations.

Nonce System

Bridge contracts use a nonce system to prevent replay attacks and ensure each bridge operation can only be executed once.

Event Verification

The relayer verifies events from both chains before executing cross-chain operations, ensuring the integrity of bridge transfers.

SBX Token

SBX is the unified token representing shares in the pool. It maintains a 1:1 peg with USD and uses a rebasing mechanism to reflect yield accrual.

Rebasing Mechanism

SBX tokens automatically rebase to reflect earned yield, maintaining the 1:1 USD peg while allowing holders to see their balance grow over time.

Yield Distribution

All yield generated from the pool is distributed proportionally to all SBX holders, regardless of which currency they originally deposited.

Current Status

✅ Production Ready - Multi-Chain Support

• ✅ Multi-currency staking on both L1 and EVM
• ✅ Direct A→B swaps on both chains
• ✅ Cross-chain token transfers
• ✅ Multi-wallet support (IOTA L1 and EVM)
• ✅ Unified basket architecture
• ✅ Shared objects (L1)
• ✅ Asymmetric withdrawal rules
• ✅ Unified APY
• ✅ Flash loan vault (L1)
• ✅ Complete frontend dApp